Liquid Nigari is used primarily as an additive for your water. It contains magnesium chloride, calcium chloride, and potassium chloride which act as an electrolyte replacement much like the electrolyte waters you find in plastic bottles on the shelves. Make it yourself with a quarter teaspoon per cup/8oz of water and and get rid of that plastic bottle for good!
Liquid Nigari is also used as a coagulant in tofu making and can be used in place of citric acid or vinegar in making ricotta and soft cheeses.
Lastly, Liquid Nigari can be used in beauty products and help clear up acne. Due to the high magnesium content it can be rubbed directly onto the skin to help with muscle recovery or restless legs.